Focused ultrasound may reduce cancer pain

A focused ultrasound with non-invasive magnetic resonance could provide relief from excruciating cancer pain, a new study has found.
When cancer progresses and spreads to the bone, patients often suffer debilitating pain.
Now, a new phase III clinical trial shows that non-invasive magnetic resonance guided focused ultrasound treatment that heats the cancer within the bone, relieves pain and improves function for most patients when other treatment options are limited.
Magnetic resonance guided focused ultrasound surgery (MRgFUS) is a technique that's been safely used to treat thousands of women with uterine fibroids.
However, "this is the first phase III study to use this technology in the treatment of cancer," said the study's principal investigator and lead author Mark Hurwitz, from the Thomas Jefferson University.

Although radiation therapy is commonly used to treat bone-related pain and effective for most patients, not all patients experience pain relief and over time those who do may have recurrence of pain.

In addition, it's possible for a patient to receive the maximum radiation dose that can be safely delivered without fully controlling the pain.
A total of 147 patients from 17 centres in the US, Canada, Israel, Italy, and Russia were enrolled in the study and randomised to undergo MRgFUS or a sham treatment.
Patients in the treatment group received focused ultrasound precisely targeted to their bone tumours to heat the tumour tissue to between 65 and 85 degrees Celsius, resulting in its destruction.

During each treatment, the patients were monitored real-time via magnetic resonance imaging (MRI) to ensure the right tissue was targeted and the right temperatures were reached while ensuring heat in surrounding normal tissues and organs remained at safe levels.
The control group underwent the same procedure but without the ultrasound device turned on. Finally, patients who did not respond to the placebo treatment within two weeks were allowed to be unblinded and offered MRgFUS.
Patients responded well to treatment, with 64 per cent experiencing either no pain or a significant reduction in their pain at three months as measured by a 2 point or greater decrease in the numeric rating score(NRS) for pain, a clinically validated measurement tool.

Many patients were able to reduce or stop use of opioid medications. Notably, most patients experienced pain relief and improved functioning within several days of treatment.
"It's clear that for many of these patients, pain has a major impact on their everyday lives. This approach offers a new way to help alleviate that pain via an out-patient non-invasive procedure," said Hurwitz.
The results were published in the Journal of the National Cancer Institute (JNCI).